1. Technical Field
The present invention relates to a measurement apparatus, a test system, and a measurement method for measuring a characteristic of a device.
2. Related Art
A conventional measurement apparatus is known that detects a defect in a device based on the quiescent current (IDDQ) of a CMOS LSI or the like. The measurement apparatus uses the fact that the power supply current does not flow in the CMOS circuit, i.e. IDDQ≈0, when the transistor is at an unchanging state of rest, to detect a defect by measuring the IDDQ current flowing when each logic vector is applied. Such a measurement apparatus is shown in Japanese Patent Application Publication No. 2006-317208.
However, the miniaturization of CMOS LSIs has caused an increase in the leak current flowing through a normal CMOS circuit. This makes it difficult to distinguish between the power supply current flowing in a defective CMOS circuit (referred to hereinafter as the “defective current”) and the leak current flowing through a normal CMOS circuit. Furthermore, the noise voltage generated by the power supply used in the measurement is converted into a noise current in the bypass capacitor connected to the device under measurement. Therefore, the defective current to be measured is buried in a noise current, so that the defective current cannot be accurately measured.